Transforming Co3O4 nanosheets into porous N-doped CoxOy nanosheets with oxygen vacancies for the oxygen evolution reaction

• Published in: Journal of energy chemistry Vol. 35; pp. 24 - 29
• Main Authors: Xu, Lei, Zou, Yuqin, Xiao, Zhaohui, Wang, Shuangyin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2019
• Subjects: Cobalt oxides; Electrocatalysts; N doping; Oxygen evolution reaction; Oxygen vacancies; Cobalt oxides; Oxygen vacancies; Oxygen evolution reaction; Electrocatalysts; N doping
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2018.09.013

Cobalt oxides have been widely investigated as promising replacements for noble metal-based catalysts for oxygen evolution reaction (OER). Herein, we, for the first time, have obtained porous CoxOy nanosheets with N-doping and oxygen vacancies by etching Co3O4 nanosheets with NH3 plasma. Comparing with the pristine Co3O4 nanosheets (1.79 V), the porous CoxOy nanosheets with N-doping and oxygen vacancies have a much lower potential of 1.51 V versus RHE to reach the current density of 10 mA cm−2. The obtained sample has a lower Tafel slope of 68 mV dec−1 than the pristine Co3O4 nanosheets (234 mV dec−1). The disclosed Co2+, which is responsible for the formation of active sites (CoOOH), N-doping and oxygen vacancies, gives rise to better performance of OER. [Display omitted] The porous CoxOy nanosheets with N-doping and oxygen vacancies were obtained by etching Co3O4 nanosheets with NH3 plasma. The disclosed Co2+, N-doping and oxygen vacancies give rise to better performance of OER.